The oral dose of elemental iron for iron deficiency should be 100 to 200 mg daily.

Although iron preparations are best absorbed on an empty stomach they can be taken after food to reduce gastro-intestinal adverse effects; they may discolour stools. The incidence of adverse effects due to ferrous sulfate is no greater than with other iron salts when compared on the basis of equivalent amounts of elemental iron.

Parenteral iron does not produce a faster haemoglobin response than oral iron provided that the oral iron preparation is taken reliably and is absorbed adequately (with the exception of patients with severe renal failure receiving haemodialysis).

Subsidised Parenteral Iron Preparations

Parenteral iron is generally reserved for use when oral therapy is unsuccessful because the patient cannot tolerate oral iron, or does not take it reliably, or if there is continuing blood loss, or in malabsorption.

Hypersensitivity can occur with parenteral iron and facilities for cardiopulmonary resuscitation should ideally be available-risk of allergic reactions increased in immune or inflammatory conditions.